Phorbol-12-Myristate-13-Acetate (PMA) Reactivates Replication from HIV-1 Latency and Induces Jurkat Cell Death

Abstract

HIV-1 has the capability to establish latency during early infection in CD4+ cells, posing a significant challenge to the efforts aimed at curing HIV-1/AIDS. One extensively explored strategy to address this viral latency is the "shock-and-kill" approach. This involves reactivating viral replication using latency reversal agents (LRAs) to induce the death of infected cells. Regrettably, no LRAs with proven effectiveness have been identified thus far. In this study, we investigated the impact of Azidothymidine (AZT) treatment interruption and the administration of Phorbol-12-Myristate-13-Acetate (PMA), a PKC activator, as shock-and-kill approaches in vitro. We employed the susceptible Jurkat cell line and utilized a sensitive real-time PCR assay along with Western blotting analysis. Our findings revealed that AZT inhibited HIV-1 replication, and its treatment interruption led to the reactivation of viral replication. This reactivation occurred through the recruitment of host transcription factors, including NFAT, NF-κBp65, Ap-1, and Sp-1. These factors facilitated HIV production via TCR-related pathways, activation of p-TEFb pathways for transcription elongation, and upregulation of Jak/Stat pathways for viral enhancement. Furthermore, we demonstrated that PMA treatment increased the levels of these transcription factors through the activation of TCR-related signaling pathways in HIV-1 infected Jurkat cells, irrespective of the AZT treatment status. PMA also induced cell death through both extrinsic and intrinsic apoptotic signaling pathways, as well as autophagy. These results suggest that PMA effectively employs the shock-and-kill approach in HIV-1 infected Jurkat cells and highlight the potential of PKC pathway activators as promising LRAs.